DSIP Canada: Research Peptide Overview

DSIP — delta sleep-inducing peptide — is a nine-residue peptide first recovered in the 1970s from the blood of sleeping rabbits. It is among the longest-studied compounds in a research peptide catalogue and, at the same time, among the least understood: after roughly five decades of work, no receptor for it has been identified and no gene encoding it has been found.

Written by the NexPept Research Team · Last updated: October 2026

This guide sets out what the compound is, what the literature does and does not establish, why the name is a poor guide to either, and how NexPept documents each batch. It is an educational overview for laboratory research purposes and is not a dosing guide.

What Is DSIP?

DSIP is a linear nonapeptide — nine amino acids, no disulfide bridges, no modifications — with the sequence Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu, written WAGGDASGE in single-letter notation. At roughly 849 g/mol it is a small, structurally plain molecule.

It was isolated in the 1970s by the Schoenenberger–Monnier group in Switzerland, from the cerebral venous blood of rabbits placed in an induced sleep state. The reasoning was straightforward: if a substance circulating during slow-wave sleep could be recovered and transferred, it might be a sleep-regulating factor. DSIP is what came out of that fractionation, and it was named for the condition it was pulled from.

That naming decision has shaped how the compound is discussed ever since, and not helpfully. If you are new to this category of material, our guide explaining what research peptides are is a useful starting point.

DSIP Properties

These are the published identifiers for the compound. Purity and batch values specific to the material NexPept ships are further down.

What Is Actually Known About DSIP — And What Isn't

This is the section that matters, and it is the one most pages about this compound leave out.

The name describes an assay, not a mechanism

"Delta sleep-inducing peptide" records where the molecule was found: in the blood of animals in slow-wave (delta) sleep. It was a reasonable label for a 1970s fractionation result. It is not a finding, it is not a mechanism, and it has never been upgraded into either. A researcher reading the name as a statement of established effect is reading something the literature does not say.

No receptor has been identified

Roughly fifty years after isolation, no receptor for DSIP has been found. Various mediators have been proposed — NMDA receptor involvement has been suggested, and an α1-adrenergic pathway was implicated in one rat pineal study — but none is confirmed. For a peptide this heavily studied, that is genuinely unusual, and it constrains what any experiment using it can conclude.

No precursor gene has been found

Beyond the missing receptor, no gene encoding DSIP or a DSIP precursor has been identified. That leaves its status as a true endogenous peptide unresolved rather than established — a significant open question for a compound named after an endogenous role.

The sleep findings do not consistently replicate

Studies on DSIP and sleep have been contradictory. Some report slow-wave sleep promotion and REM suppression; others find no correlation at all. Notably, stronger effects have been reported for synthetic analogues of DSIP than for DSIP itself. A 2006 review in the Journal of Neurochemistry summarised the state of play in its title: "Delta sleep-inducing peptide (DSIP): a still unresolved riddle."

None of this makes DSIP uninteresting as a research compound — an unresolved question is a reason to study something. It does mean that any supplier page describing confident effects is describing something other than the published record, and that a researcher designing work with this peptide should plan around the absence of a known target rather than assume one.

Research Focus Areas

In controlled laboratory environments, DSIP appears in work on:

• Sleep-architecture studies in animal models, including slow-wave and REM measures
• Attempts to characterise a binding target or transport mechanism
• Peptide stability and blood–brain barrier permeability research
• Comparative work against synthetic DSIP analogues
• Neuroendocrine and stress-response models
• Analytical method development, where a small unmodified peptide is useful as a reference

All of this is preclinical and confined to experimental contexts. Interpretation should be limited strictly to the laboratory data in question, and — given the above — held more loosely than for a compound with a characterised target.

How DSIP Compares With Other Short Neuro Research Peptides

DSIP sits in the same catalogue category as several other short peptides, but it is the outlier in one specific respect.

Semax and Selank are analogues of molecules whose biology was already mapped, which gives their research a defined starting point. DSIP and Pinealon do not have that. All four sit under neuro research in our catalogue.

Purity, Batch Data and Documentation

DSIP has a documentation problem that is specific to it, and worth spelling out.

Because no receptor has been identified, there is no functional assay that can confirm you have the right compound. For a peptide with a characterised target, a binding assay offers a second line of evidence — if it binds as expected, it is probably what the label says. With DSIP there is nothing to bind to. Analytical chemistry is not merely the best check available; it is the only one.

That raises the stakes on identity confirmation. DSIP is also an easy sequence to synthesize — nine residues, four of them glycine or alanine, no modifications — so high HPLC purity figures are cheap here and say less than they appear to. Mass spectrometry confirming the molecular weight is the check that matters, because it is the only one that distinguishes the right nonapeptide from a wrong one.

"COA available on request" is the most over-claimed phrase in this market. A certificate worth relying on names the testing laboratory, carries a lot number matching the vial in your hand, states the analytical method, and shows the chromatogram rather than a number someone typed. We publish ours instead of supplying them on request, so the material can be checked before an order is placed.

Identity and purity are confirmed by HPLC and mass spectrometry before a lot is listed, and the certificate stays published in our COA library after the batch sells out — so a result recorded against an old lot can still be traced back to its report. All new batches additionally carry endotoxin testing, which matters for cell-based work where endotoxin can confound a result independently of chemical purity, and the most-ordered products also carry heavy-metal testing.

Storage and Handling

Lyophilized peptide material is comparatively stable, but handling after delivery affects integrity more than most buyers expect. General laboratory considerations include:

• Storage cool and dry, avoiding repeated temperature cycling
• Protection from moisture and prolonged light exposure — the tryptophan residue at position 1 is the most light-sensitive amino acid in the sequence, so amber or opaque storage is worth the small effort
• Recording the lot number against your own inventory, so any later question about a result traces back to a specific batch and its report
• Handling under institution-approved protocols

Lyophilized powder is considerably more stable than peptide in solution, and researchers should defer to their own institution's validated protocols rather than a general guideline. More detail is in our guide to storing research peptides. NexPept does not supply preparation, reconstitution or handling instructions; those are determined by qualified personnel under your own protocols.

Sourcing DSIP in Canada

Four things are worth checking before ordering anywhere. They apply to any supplier rather than to this compound specifically.

Documentation

Batch-specific reports, published rather than promised, with a lot number that matches your vial. For DSIP in particular, check that the certificate confirms identity by mass spectrometry — for the reason set out above, it is the only verification route available for this compound. One generic certificate covering a whole catalogue tells you nothing about what arrived.

Fulfilment

A stated Canadian location and courier. Material crossing the border is subject to customs holds nobody can give you a date for, and spends longer in uncontrolled conditions. Our orders ship from Ontario by tracked Canada Post — details on the shipping page.

Positioning

Research-use framing throughout. This matters more for DSIP than for almost anything else in a catalogue, because the compound's own name invites the claim. A supplier describing sleep benefits, dosing protocols or timing advice for a peptide with no identified receptor and contradictory published findings is not reporting the literature — and that tells you how the rest of the operation is run.

Pricing

Analytical testing costs money per lot. A catalogue priced well below everyone else has usually removed a cost somewhere, and testing is the easiest one to remove while still describing material as tested. For a wider walkthrough of evaluating a domestic supplier, see our Peptides Canada guide and our guide to buying research peptides in Canada.

Common Questions About DSIP

Key Takeaways

• DSIP is the nonapeptide WAGGDASGE, CAS 62568-57-4, isolated from rabbit cerebral venous blood in the 1970s
• Its name records the assay it came out of, not a demonstrated mechanism
• No receptor and no precursor gene have ever been identified, after roughly fifty years of study
• Published sleep findings are contradictory, and a 2006 review called it "a still unresolved riddle"
• With no known target there is no functional assay, so mass spectrometry identity confirmation is the only verification available
• The current NexPept lot, NP-DSIP-02, tested at 99.13% by HPLC on August 5, 2026, certificate published up front
• It is not authorized by Health Canada and is supplied for laboratory research use only

Peer-reviewed literature on this compound is indexed on PubMed, and the full NexPept catalogue of lab-tested compounds is available here.